1. Field of the Invention
This invention relates to the field of shade umbrellas and more particularly to an adjustable shade umbrella.
2. Description of the Related Art
Umbrellas are often used to provide welcome shady relief from the hot sun in areas such as beaches, swimming pools, parks and patios. Some sun umbrellas are designed to be used in conjunction with beach chairs or other outdoor chairs to provide shade for a person sitting in the chair. As the day passes, however, the location of the sun relative to the chair changes, thus necessitating an adjustment in the placement of the umbrella. If the umbrella is not adjustable, the person using the chair may have to repeatedly move the chair as the day passes to maintain adequate shade because of the changing angle of the sun's rays. Moving the chair is inconvenient and frustrating.
U.S. Pat. No. 4,871,141, to Chen, discloses an adjustable umbrella support which is adapted to be attached to a beach chair. The umbrella support attaches to a tubular side frame of the beach chair and the rod of the umbrella has flexible portions to allow adjustment of the umbrella without moving the chair.
This design, however, has a number of key limitations. For instance, since the support is located on the side frame member, the support is likely to get in the way of a user's arm or shoulder when the user is seated in the chair. Also, when the umbrella is adjusted to a desired shade-producing position, the bending umbrella shaft is likely to be positioned at least partially in front of the user's face and chest. Such placement is uncomfortable and inconvenient. Additionally, since the support is mounted to a side of the chair, the umbrella's range of adjustment is limited and some sun angles cannot be adequately shaded without removing the support and reinstalling it on the other side of the chair. Further, the flexible portions of the umbrella rod may become loose over time; thus, the umbrella may be unable to maintain a chosen position without sagging. Also, breezes may change the umbrella's position.
Some beach chair umbrella embodiments are attached to a beach chair arm rest by a C-clamp or other clamping means. This is undesirable because, first of all, the attachment uses the arm rest and is thus in the way of the person sitting in the chair. Also, such attachment methods have proven somewhat unstable, particularly in windy conditions. The gripping member is also subject to wear, requiring that the clamp be secured tighter and tighter to the chair over time. Further, this clamping means may damage the beach chair.